JPH11278104A - Control device for torque or the like and control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To load engine output required for a motive power transmission device by securing internal resistance of an engine and torque required for auxiliary equipment even in the case when the maximum value of engine fly wheel torque exceeds allowable torque of a drive device at low speed travelling. SOLUTION: This drive device 10 has a driving system 11 to be driven by a motive power source 12 such as an engine, and includes a plural number of stages of transmissions 14 and a final speed reducing means 19, etc. Additionally, it has a means capable of protecting the driving system 11 even in the case when the engine is set at a value lower than the maximum allowable torque corresponding to a state of generating the maximum torque or torque large enough to damage the driving system in a state where allowable torque of the driving system selects a low gear ratio. Consequently, torque to be loaded on the transmissions 14 is most properly controlled to protect the driving system 11 of a vehicle while securing engine torque required in consideration of internal resistance of auxiliary equipment and the engine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device and a control method for limiting a torque applied to a drive device of a vehicle. In particular, the present invention relates to a drive device for a vehicle including an electronically controlled engine and a drive system having a certain limit on torque transmission capability (allowable torque). Then, based on the values of the control parameters (for example, the selected gear, vehicle speed, etc.) representing the driving state, it is monitored whether or not excessive torque exceeding the allowable torque is applied to the drive system, and the transmission capacity of the drive device is monitored. The present invention relates to control means of a drive device of a vehicle, such as limiting an engine output torque (flywheel torque) during an operation state in which a large torque exceeding is applied. Further, the present invention relates to control of an engine flywheel torque for protecting a drive system of a vehicle, and a necessary torque value is considered in consideration of control parameters related to other engine torques such as engine accessories. To decide. The present invention also relates to U.S. application Ser. No. 08/5, assigned to Eaton Corporation.
No. 60,458, which is related to the title of the invention "Torque control of drive device".

[Prior art]

2. Description of the Related Art As a vehicle drive device, a drive device including a fuel control type engine such as a diesel engine and a drive system including a multi-stage change gear type transmission and a drive axle has been known. For example, regarding a drive unit for a vehicle and its components, U.S. Pat. Nos. 3,105,395, 3,448,635, 4,361,060, and
Nos. 4,977,972, 4,595,986, 5,033,795 and 5,305,213, the details of which are incorporated herein by reference.

An electronically controlled engine including an engine control computer for exchanging information with various vehicle components and control devices such as a transmission control device via an electronic data link has been well known. . As an example,
Engine controls and data links that operate according to industry standard protocols such as SAE J-1922, SAE J-1939, and ISO 11898.

[0004]

However, the conventional power transmission device has the following problems. For example, if the allowable torque of the power transmission device is set on the basis of the state where the maximum torque is applied at the time of low-speed operation, over-quality occurs in many other operating states. Further, when the torque is set based on the torque in an extremely general operation state, the engine output at the time of low-speed operation becomes a torque of a maximum class or a torque that “fails” the power transmission device.

A control device for controlling an engine torque value (mainly a gross value of the engine torque) for protecting a power transmission device of a vehicle for the purpose of solving the above-mentioned problems is better known in the prior art. U.S. Pat.No. 5,679,09
No. 6 and the aforementioned U.S. application Ser. No. 08 / 560,458. These are included in this description as references.

[0006] However, even with the engine torque control device according to the prior art described above, sufficiently satisfactory control has not been performed. That is, in these conventional control devices, control parameters other than the flywheel torque, such as the gross value of the engine torque, are controlled. Therefore, the driving of the engine accessories and the internal resistance of the engine are taken into consideration. However, the required power of the engine cannot be applied to the power transmission device.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has a threshold value indicating that one or more torques exceeding a predetermined allowable torque are applied. It is an object of the present invention to solve the problems of the prior art by providing a control unit of a driving device for monitoring a comparison value with one or a plurality of control parameters. In the present invention, if it is determined that the driving state is such that a large torque exceeding the allowable torque is applied to the drive train, the engine output, especially the torque related to the engine flywheel (referred to as engine flywheel torque) is limited. Is done. Preferably, the engine is SAE J-1922, SAE J-
An electronically controlled engine that exchanges information via an electronic data link operating according to an industry standard protocol such as 1939, ISO 11898, etc., having one or more torque control modes.

As is well known in the industry,
In particular, as mentioned in the industry standard protocol,
The child control engine is operated in particular in four operating modes
It is. One of them is the engine control unit ECU
Is the engine torque (gross) set on the data bus.
Value) has been exceeded,
This is the torque limit mode. In this mode of operation, the engine
Torque value (T _EGDrive while restricting)
The device can be protected. However, the operation mode
Overcoming the internal resistance of the engine and
The torque required to drive engine accessories is also limited
May be done. In the present invention, the engine fly
Torque (T_FW) By limiting
It is possible to prevent the shortcomings of the technology and to protect the drive.
it can.

[0009] That is, an object of the present invention is to provide an improved control method and control device for limiting a torque applied to a drive device of a vehicle. And
Even if the low-speed gear is selected and the vehicle is running at low speed, and the maximum value of the engine flywheel torque exceeds the allowable torque of the drive unit, it overcomes the internal resistance of the engine, An object of the present invention is to secure a torque required to drive engine accessories.

The above and other objects and advantages of the present invention can be understood by referring to the following detailed description and the accompanying drawings.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 schematically illustrates a typical vehicle drive 10, such as a heavy duty truck. The drive device 10 has a drive system 11 driven by a power source 12 such as a generally known diesel engine. Further, the drive system 11 includes a plurality of change gear type transmissions 14 which are drivingly connected to the engine 12 via the main clutch 16 which is normally engaged, and final reduction means 19 such as a drive axle and a transfer case. And an output shaft 18 connected thereto.
The crankshaft 20 of the engine 12 drives the input side member 22 of the main clutch 16. The input side member 22 includes a transmission
The output side member 24 fixed to the 14 input shafts 26 can be engaged or disengaged by frictional force. The main clutch 16 is controlled to be engaged or disengaged by a manual or automatic controller 27. The transmission 14 also preferably has a forward speed of 7 th to 18 th speed and has a manual shift lever 28 of a shift bar housing or shift shaft mechanism 29.
Is operated to perform a shift operation.

The throttle pedal monitoring means 30 monitors the position or the amount of depression of the throttle pedal 32 and outputs a signal 34 indicating the position or the amount of the depression. The engine 12 includes a control device. This control device is a control device controlled by a microcomputer.
Preferably, the information exchange is performed via the electronic data link DL, and the fuel supply amount is controlled in accordance with a command received via the data link. The command is typically issued by a driver to increase the throttle opening, to achieve a desired engine speed, or
This is for obtaining the maximum output torque (that is, the maximum flywheel torque).

A system controller 48 controlled by a microcomputer.
(In-vehicle computer) is a throttle pedal monitoring means
30 and a signal GR from the selected gear ratio detection sensor 54 and, if necessary, a signal OS from the output shaft speed sensor 56 (these signals are collectively referred to as an input signal 50).
And ), Process each input signal 50 according to a preset logic rule, and output a command output signal 52. Each command output signal is transmitted to the engine control device 36 via the data link DL.
Sent to

In the embodiment of the present invention, the allowable torque of the drive system 11 is such that a low gear ratio is selected and the engine generates the maximum torque or a torque that causes the drive system to "fail". And a means capable of protecting the drive system 11 even when the torque is set to a value smaller than the maximum allowable torque.

In the present embodiment, the maximum allowable torque of the drive system 11 is determined in consideration of the cost so that the value can avoid a failure in a general operation state. Then, in an exceptional driving state where an excessive torque is applied, as shown in FIG. 2, the control parameters such as the selected gear ratio (GR) and the vehicle speed (obtained from the output shaft speed OS) are detected. Then, the detected value is compared with a threshold value REF.
It is to be noted that, when torque enough to cause a failure is applied to the drive train, these are the values of the corresponding control parameters, and the REF value of the selected gear ratio GR and the REF value of the vehicle speed OS are determined in advance. ing.

For example, when the selected gear ratio is lower than a low gear (low gear) and the vehicle speed is lower than 1.79 m / s (4 mph), the maximum output torque of the engine 12 is used to protect the drive train 11. Is limited to a value smaller than the maximum allowable torque of the drive system 11.

That is, the output torque of the engine is changed by the control parameter. For example, assuming a maximum allowable torque of 150% of the rated output torque, if the selected gear has a high reduction ratio (for example, 12: 1 or more), the maximum output torque of the engine will be 100% of the rated output torque. Limited to% value. If the selected gear ratio is 10: 1, the value of the maximum output torque of the engine is limited to 120% of the rated output torque value. When the selected gear ratio is less than 10: 1, the engine output torque is not particularly limited.

FIG. 2 shows a flowchart of a control method or apparatus according to an embodiment of the present invention.
In such a procedure, the GR REF value and the OS REF value are determined, and the maximum output torque related to the engine flywheel torque (T _FW ) is determined from the detected GR value and OS value. (FIG. 3 shows a procedure for obtaining the engine flywheel torque T _FW as a function of GR and using this T _FW as the value of the maximum output torque.)
R) is compared with the corresponding REF value, and the maximum output torque _TFW is controlled based on the comparison result.

An apparatus having a similar configuration is disclosed in US Pat. No. 5,679,096, which is incorporated herein by reference. Preferably, the vehicle has SAE J-19
22, It has an electronic data link in a format compatible with industrial standard protocols such as SAE J-1939.

US Pat. Nos. 5,509,867, 5,582,069, 5,620,392 and 5,620,392, which are incorporated herein by reference.
US Pat. No. 5,620,558 exemplifies a vehicle that utilizes the value of the engine flywheel torque (T _FW ) as a criterion in a manner similar to or similar to the present invention. In these cases, the determination is made based on the following relational expression. T _EG = T _FW + T _BEF + T _ACCES + T _ACCEL

Here, T _EG : gross value of engine torque T _FW : engine flywheel torque value T _BEF : basic resistance value of the engine (torque for overcoming the internal resistance value of the engine, for example, water pump, oil pump Includes torque for driving engine accessories installed in factories, etc.) T _ACCES : Accessory torque value (torque for operating accessory of vehicle such as air conditioner, fan, lighting etc.) T _ACCEL : Torque value for accelerating the engine. It is calculated based on the acceleration and deceleration of the engine, the moment of inertia (I) of the engine, and the like.

The instantaneous values corresponding to the gross value of the engine torque (T _EG ) and the basic resistance value of the engine (T _BEF ) are:
Obtained via the data link. The torque value (T _ACCEL ) for accelerating the engine detects the acceleration of the engine (passively) and calculates the moment of inertia (I) of the engine.
Is measured. Moreover, adjunct torque value (T _ACCES) is a vehicle traveling, the transmission is in the neutral position, when the engine is a substantially linear deceleration, net value of the engine torque (i.e. T _EG −T _BEF ).

That is, the control device and the control method according to the present embodiment consider a value of (T _FW ), which is a constantly updated control parameter and indicates the engine flywheel torque, as the control parameter. .

According to the value of the engine flywheel torque (T _FW ) instead of the gross value of the engine torque, the driving force for accessories driven by the engine is taken into consideration and the internal resistance of the engine is taken into consideration. Therefore, the torque applied to the transmission is optimally controlled so as to protect the driving system of the vehicle while securing the necessary engine torque. The above is particularly effective when the vehicle travels at a low speed, and more torque for acceleration can be given to the drive device without causing the drive device to fail.

Now, the present invention has been described in detail with reference to the above embodiments. However, the present invention is not limited to the above embodiments, and various changes can be made without departing from the scope of the claims. It will be understood that

[Brief description of the drawings]

FIG. 1 is a schematic view showing a vehicle driving device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a procedure for controlling a torque applied to a drive device in the embodiment of the present invention.

FIG. 3 is a flowchart showing a part of a procedure for controlling a torque applied to a drive device in the embodiment of the present invention.

[Explanation of symbols]

10 Drive unit 11 Drive system 12 Engine 14 Change gear type transmission 36 Control unit 48 System control unit 50 Input signal 52 Command output signal DL Electronic data link GR Gear ratio signal OS Output shaft speed signal T _FW engine flywheel torque

 ──────────────────────────────────────────────────続 き Continuation of front page (71) Applicant 390033020 Eaton Center, Cleveland and Ohio 44114, U.S.A. S. A.

Claims (13)

[Claims] 1. A program unit for an in-vehicle computer (48) for controlling a vehicle drive device (10) including a fuel control type engine (12) and a drive system (11), The type engine (12) is drivingly connected to the drive system (11), a maximum output torque is set, and
An engine control device controlled by a microcomputer that operates in response to a command signal for controlling a fuel supply amount; the engine control device has at least one operation mode for limiting a gross value of engine torque; The system (11) has a multi-stage change gear type transmission (14) and a drive axle (19), and its maximum allowable torque is a torque load assumed in an operation state preset in the drive system. The value is set to a value lower than the load assumed under an operation state where an excessive torque is applied and the maximum engine flywheel torque, and the on-vehicle computer (48) relates to an operation state of a drive system. It is intended to receive the value at which the input signal of the control parameters (50), the program unit is controlled indicative of engine flywheel torque (T _FW) Determine the value of the parameter, during the operating state in which excessive torque is loaded on the drive system, compare the detected value related to the control parameter with a corresponding threshold value, the detected value related to the control parameter , Indicating that the driving system is in an operation state in which excessive torque is loaded,
A program unit, wherein the engine control device limits the engine flywheel torque to a maximum allowable torque of the drive train or less. 2. The program unit according to claim 1, wherein the value of the engine flywheel torque is a function of a gross value of the engine torque. 3. The program unit according to claim 2, wherein the control parameter represents a selected gear ratio (GR). 4. The control parameter is a vehicle speed (OS).
3. The program unit according to claim 2, wherein 5. The program unit according to claim 2, wherein said engine control device exchanges information via an electronic data link. 6. The program unit according to claim 2, wherein the change gear type transmission is a manual transmission. 7. The in-vehicle computer is provided in the engine control device.
The described program unit. 8. A control method for a vehicle drive device (10) including a fuel control type engine (12) and a drive system (11), wherein the fuel control type engine (12) includes a drive system. (1
1) is drive-coupled with, the maximum output torque is set,
A microcomputer-controlled engine control device that operates in response to a command signal for controlling a fuel supply amount, the engine control device having at least one operation mode for limiting a gross value of engine torque; 11) has a multi-stage change gear type transmission (14) and a drive axle (19), and adjusts the maximum allowable torque thereof to an engine output torque less than or equal to the maximum output torque, which is set in advance in a drive system. In the operating state specified by the gear ratio selected by the transmission, the value is set to a value lower than the assumed torque load, and the value of the engine flywheel torque, which is the value of the control parameter, is determined as a function of the gross value of the engine torque. Detecting a control parameter representing a gear ratio selected by the transmission, and determining the control parameter as a function of the gear ratio selected by the transmission. Controlling the torque applied to the drive device, wherein the engine controller limits a gross value of the engine torque to a value corresponding to the engine flywheel torque determined in the step (a). 9. The method of controlling a torque applied to a drive device according to claim 8, wherein the engine control device is controlled by a microcomputer and exchanges information via an electronic data link. 10. The method of controlling torque applied to a drive device according to claim 8, wherein the speed change device is configured to perform a speed change manually. 11. A control device for a vehicle drive device (10) including a fuel control type engine (12) and a drive system (11), wherein the fuel control type engine (12) includes the drive system. (1
1) is drivingly connected to the engine, and has a maximum flywheel torque, a microcomputer-controlled engine control device that operates according to a command signal for controlling the fuel supply amount, and the engine control device is configured to reduce the engine torque. It has at least one operation mode for limiting a gross value, and the drive system (11) has a multi-stage change gear type transmission (14) and a drive axle (19), and has a maximum allowable torque. In the operating state specified from the gear ratio selected by the transmission and the engine output torque equal to or less than the maximum output torque, which is set in advance in the drive system, it is set to be lower than the assumed torque load. Means for determining a value of a control parameter representing an engine flywheel torque (T _FW ) as a function that changes according to a gross value of the engine torque Means for detecting a value of a control parameter representative of a gear ratio selected by the transmission; and engine torque for a value of engine flywheel torque determined as a function of the gear ratio selected by the transmission. A control device for controlling a torque applied to a drive device, wherein the engine controller includes means for restricting the engine flywheel torque by limiting a gross value of the drive device. 12. The control device according to claim 11, wherein the engine control device is controlled by a microcomputer and exchanges information via an electronic data link. 13. The control device according to claim 11, wherein the transmission is a manual transmission.